Tosa Ken was (and still is) known to be quiet, courageous, and deadly. In the mid- to late 1800s and early 1900s, Mastiffs, Saint Bernards, Great Danes, and Bulldogs were imported into Japan to be bred with native dogs in the hopes of creating the ultimate fighting dog. Developed in the old Tosa province, now known as the Kochi prefecture, the Tosa Ken dog breed almost went extinct during World War II but was saved by fanciers. The Tosa Ken is revered in Japan; he is the Sumo wrestler of the canine world.

Tosa Ken dogs stand 21.75 to 23.5 inches or taller and usually weigh between 100 and 200 pounds, although some may be heavier. The head is large and blocky, the eyes are brown, the nose black, and the ears medium-sized and dropped. The body is strong, muscular, and slightly longer than the dog is tall. The tail hangs naturally to the hocks and is never carried over the back. The dog’s skin is loose, with pendulous lips, a large flap of skin that hangs beneath the chin, and wrinkles on the forehead. The coat is short and dense. Tosa Ken dogs may be red, brindle, black, or brown. The coat should be brushed weekly with a soft bristle brush or curry comb.

The Tosa Ken is an athletic, agile dog breed which needs daily exercise. He needs a couple of brisk, long walks and a chance to run and play. Socialization is very important for this dog breed. Tosa Kens are very watchful of strangers and need a lot of socialization to other people as puppies and on into adulthood.

Tosa Ken dogs are still used in Japan for ritualistic dog fights and retain those instincts. Training this dog breed is not difficult; Tosa Kens are eager to learn and very willing to please. The Tosa Ken needs an experienced dog owner who can be the dog’s leader. The owner must be willing to take the time to socialize and train the dog. The dog may live peacefully with other family dogs when raised with them but is usually aggressive toward unknown dogs. Health concerns include hip and elbow dysplasia, eye problems, bloat, and torsion.